From my knowledge, Verbal contracts are still binding contracts. In other words, Yes you would have to pay for that month unless you and the landlord agreed on other terms.
I hope this doesnt sounds mean, but put yourself in your landlords shoes. While thinking like the Landlord, think about what you would have to do to get this property rented out asap in order not a lose a months rent when you thought you were going to have it rented out.
Just some food for thought
Let me know how it works out
Indalecio "Andy" Del Real
See link to CA landlord/tenant law http://www.dca.ca.gov/publications/landlordbook/catenant.pdf
Go to page 49 of that document regarding moving out
"Tenant's notice to end a periodic tenancy.
To end a periodic rental agreement (for example, a month-to-month agreement) you must give your landlord proper written notice before you move.
You must give the landlord the same amount of notice as there days between rent payments. This means that if you pay rent monthlt, you must give the landlord written notice at least 30 days before you move."
I totally agree with Andy. The most important thing is to communicate with the landlord because they may not mind you breaking the verbal agreement, especially since 6 days earlier they weren't expecting your tenancy past the end of the month.
Better Homes Realty- Elite